Intramolecular forces are harder to break because it would be breaking the actual bonds between atoms. Intermolecular forces are forces between different molecules and include things like London dispersion forces, Van der Waals forces, and dipole-dipole interactions and are easier to break.

you can also think about it in this way: intramolecular forces include the overlapping of orbitals and the actual share/giving of e-. It will be much stronger than just "interactions" of molecules - the intermolecular forces

Intermolecular forces are weaker than intramolecular forces. Therefore it would be easier to break the bond between atoms that make up a molecule than to separate molecules. Intramolecular forces also consist of weak forces such as London dispersion and Van der Waals.

Intramolecular forces are much stronger as they are heavily involved with sharing or giving/gaining electrons instead of just having interactions between molecules such as intermolecular forces such as DD forces